强流束传输中束晕的形成

HALO FORMATION OF INTENSE BEAM IN PERIODIC TRANSPORT SYSTEM

放射性洁净核能系统的强流加速器中，绕束核外围的束晕最容易损失在机器壁上，产生超标的放射性。弄清束晕形成的机制，寻找尽量降低束损的加速器设计方法，对于建造这样的强流加速器至关重要。文章从束晕理论模型和方法等方面进行了综合论述，并在其中给出一些初步研究结果。最后，讨论了束晕研究中尚待解决的课题。

In the intense current proton accelerators for driving the radioactive clean nuclear system,the halo particles are most easily lost on the wall of the accelerator,resulting in radioactivity strong enough to exclude the access of workers to the machine for necessary maintenance and to damage some of the elements of the machine.Therefore it is very essential to understand the mechanism of the halo formation for the correct design of this kind of accelerators.In the paper,the recent advance in the halo studies is introduced at first. And then the halo formation in periodic transport system is investigated by means of single particle beam core model. Finally,some other approaches to the issue are discussed.